@vwbusguy notice the white zigzack line? it’s called stabilimentum, according to wikipedia its purpose is unknown, there are a bunch of theories: https://en.m.wikipedia.org/wiki/Stabilimentum
I actually observed how the spider wrapped up its prey in it. It seems that it’s kind of a silk depot so the spider doesn’t have to produce on the spot when something flies into the net.
I could not find this explanation anywhere 🤔
@mrv Apparently, some So Cal orb weavers do this, too, but not the ones around our house 😅.
@mrv We're both right! A wasp spider is a kind of orb weaver.
Spider orb webs are multifunctional structures, the main function of which is to dissipate the kinetic energy of the impacting prey, while minimizing structural damage. There is no single explanation for their remarkable strength and ductility. However, it is clear that topology is decisive in the structural performance upon impact and the arrangement of the different silk threads in the web must also exert an effect. The aim of this study is to show how a slight variation in the geometry markedly affects the prey-capture ability of spider orb webs. The study is focused on the secondary frame, a thread interposed between radial and primary frame strands, the importance of which has not been examined until now. The simulation of the impact performance of webs using different lengths of the secondary frame clarifies its structural role, which has proven to be decisive. Furthermore, the study explains why secondary frame threads of moderate length, as commonly encountered, enable the capture of prey with higher energy without a marked increase in the volume of silk used.
mrv
Scott Williams 🐧
